U.S. patent number 5,160,515 [Application Number 07/764,539] was granted by the patent office on 1992-11-03 for aspiration unit for conditioning air during rail car unloading of perishable food products.
This patent grant is currently assigned to CPC International Inc.. Invention is credited to David Houldey, John L. Nelson.
United States Patent |
5,160,515 |
Nelson , et al. |
November 3, 1992 |
Aspiration unit for conditioning air during rail car unloading of
perishable food products
Abstract
A rail car unloading aspiration unit includes a rail car nozzle
for providing air conduits for feeding conditioned air to the rail
car and for withdrawing air therefrom, ambient air being drawn
between a weather shield, hood or cover and a fan chamber mounted
on a heating chamber which forces ambient air to pass through a
filter and be heated within the range of approximately 77.degree.
F.-95.degree. F. The heated air is passed in proximity to ultra
violet lamps after which the air is directed into the rail car
nozzle and expelled into the interior of the rail car head surface
above the product being unloaded. During the time that power is
applied to the aspiration unit, the fan forces air to be drawn into
the unit and conditioned, and the ultra violet lamps remain on.
However, the heaters are selectively activated or deactivated as a
function of the temperature of the incoming air in order to
maintain the temperature of the air within the desired ranged prior
to being exposed to the ultra violet lamps.
Inventors: |
Nelson; John L. (Naperville,
IL), Houldey; David (London, CA) |
Assignee: |
CPC International Inc.
(Englewood Cliffs, NJ)
|
Family
ID: |
25070998 |
Appl.
No.: |
07/764,539 |
Filed: |
September 24, 1991 |
Current U.S.
Class: |
96/224; 220/745;
422/173; 422/24; 55/310; 55/385.4 |
Current CPC
Class: |
B61D
5/004 (20130101); B61D 27/0027 (20130101) |
Current International
Class: |
B61D
27/00 (20060101); B61D 5/00 (20060101); B01D
046/00 () |
Field of
Search: |
;55/385.4,279,267,310
;422/24,173 ;220/745 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Nozick; Bernard
Attorney, Agent or Firm: Brooks Haidt Haffner &
Delahunty
Claims
I claim:
1. Rail tank car unloading aspiration unit for conditioning air
received within the headspace inside a rail tank car during removal
of the contents of the rail tank car and replacement of the removed
contents with conditioned air, the unit comprising an air transfer
housing portion configured and dimensioned to be received within an
access port in the roof of a rail tank car, and including inlet
conduit means for directing conditioned air into the headspace and
outlet conduit means for removing air from the headspace; cover
means for covering the unit; an intake means for admitting ambient
air into the unit; conditioning means between said cover means and
said air transfer portion for conditioning the ambient air by
heating the air to a temperature within a predetermined range and
exposing the air to electromagnetic radiation; and air movement
means for drawing ambient air through said air intake means and
expelling the conditioned air through said inlet conduit means
after passage of the ambient air through said conditioning
means.
2. The rail tank car unloading aspiration unit as defined in claim
1, further comprising temperature regulating means forming part of
said conditioning means for regulating the heating of the ambient
air to a temperature within the approximate range of 77.degree. F.
to 95.degree. F. as the ambient air passes through said
conditioning means.
3. The rail tank car unloading aspiration unit as defined in claim
1, further comprising temperature regulating means forming part of
said conditioning means for regulating the heating of the ambient
air to a temperature within the approximate range of 85.degree. F.
to 95.degree. F.
4. The rail tank car unloading aspiration unit as defined in claim
1, wherein said conditioning means includes ultra-violet lamps for
producing the electromagnetic radiation in the form of ultra-violet
light, whereby the heated ambient air is exposed to ultraviolet
light as it passes through said conditioning means.
5. The rail tank car unloading aspiration unit as defined in claim
1, wherein said air movement means comprises a blower fan for
drawing ambient air into the unit through said air intake means and
forcing the ambient air to move through aid conditioning means and
into the rail tank car through said air transfer portion. and
6. The rail tank car unloading aspiration unit as defined in claim
1, wherein said conditioning means includes heating means and
irradiation means arranged along the direction of flow of the
ambient air as it moves from said air intake means to said air
transfer portion, said heating means being upstream and said
irradiation means being downstream relative to each other along
said direction of ambient air flow within said conditioning means,
whereby the ambient air is heated prior to being irradiated.
7. The rail tank car unloading aspiration unit as defined in claim
6, wherein said irradiation means comprises at least one
ultra-violet lamp for exposing the heated ambient air to
ultra-violet light.
8. The rail tank car unloading aspiration unit as defined in claim
7, wherein said inlet conduit means is downstream of said at least
one ultra-violet lamp along the direction of flow of the ambient
air, whereby the exposure of the ambient air to ultra-violet light
is optimized.
9. The rail tank car unloading aspiration unit as defined in claim
8, wherein said inlet conduit means comprises a plurality of air
inlet tubes, a plurality of ultra-violet lamps being provided each
one associated with another air inlet tube and being positioned
proximate to and upstream of the associated air inlet tube relative
to the direction of flow of the ambient air, whereby the exposure
of that portion of the ambient air directed into each air inlet
tube to ultra-violet light is optimized.
10. The rail tank car unloading aspiration unit as defined in claim
8, further comprising filter means between said air intake means
and said blower means for filtering the incoming ambient air and
removing pollutants and contaminants therefrom.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention generally relates to apparatus for purifying and
sterilizing ambient air, and more specifically to an aspiration
unit for conditioning ambient air during rail car unloading of
perishable food products.
2. Description of the Prior Art
Perishable food products are often shipped in rail cars to bulk
break stations. At these stations, the rail cars are unloaded into
stainless steel tank trucks, which in turn deliver the food
products to the ultimate customers. These break stations act as
distribution points for varying perishable food products, such as
corn syrup products. When the rail cars arrive at a break station
for off-loading into trucks, the rail car must be properly vented.
Trucks are connected via hoses to the bottom of the rail car and a
product in liquid form, such as syrup, is pumped from the rail car
to the truck. When this occurs, air must be supplied to the
interior of the rail car to replace the syrup removed from the car.
If the vent structures or access ports at the top of the rail car
is merely opened to allow ambient air to flow in to avoid a vacuum
in the head space above the liquid product being unloaded, various
pollutants, including dust, bees, insects, air born yeast or mold
spores, can enter into the car and contaminate the syrup.
Furthermore, several days could pass before the rail car is again
unloaded into a different truck at the same location. During this
intervening time, cold air introduced into the rail car in the
presence of warm syrup causes condensation to take place. The
condensation on the metal surfaces inside the car causes dripping
and provides areas for high potential of microbiological growths
which leads to mold and bacteria formation.
In U.S. Pat. No. 4,896,590 to Groos, a railroad hopper car vent is
disclosed which permits filtered air to be drawn into the rail car
to take the place of the material that is being discharged.
However, Groos merely teaches the use of a railroad hopper car vent
that relies on a filter for removing contaminants from the ambient
air prior to being admitted into the rail car. See also U.S. Pat.
No. 4,315,579 to Martin, Jr. which discloses a venting and
filtering mechanism for a milk tank vent and which utilizes a sheet
of filter material secured to the closure member or manhole cover
to prevent entry of contaminants into the interior of the tank.
U.S. Pat. No. 3,326,111 to Stevens also dislcoses a removable
filter on a vent structure for a covered hopper railway car. The
circulation of heated air through a railway car is disclosed, the
heated air being fed into the bottom of the hoppers and exhausted
at one end of the car. A shielding stream of electrically heated
air is admitted at the other end of the car near the roof which
flows along the roof to prevent moisture laden circulated air from
striking the cold roof directly, and thus preventing condensation.
The railway car described, however, is primarily designed to remove
excessive moisture released by fruits and vegetables. Excessive
moisture in the railway car, resulting from the respiration of such
fruits and vegetables, can damage the product being
transported.
It is also known to provide portable apparatus for heating or
cooling ambient air outside of a car for providing the heated or
cooled air to the inside of the car. See, for example, U.S. Pat.
No. 1,811,529 to Barstow et al. which discloses a portable
apparatus for conditioning perishable products in a railway car.
The apparatus provides a pre-ripening gas and provides for
maintenance of desired conditions of temperature and humidity. U.S.
Pat. No. 1,921,178 to Wood discloses a temperature control
apparatus installed outside a railway car. Here, the apparatus has
a fan and cooling coils across which air is blown before entering
the car. The objective in Wood is to maintain the cargo being
transported within predetermined temperature ranges, below a
predetermined temperature but not so low that the goods may be
frozen or otherwise damaged. Provision is, therefore, made for
cooling or heating the air directed into the refrigerator car to
compensate for the outside or ambient air temperature.
While the earlier approaches, therefore, have recognized that air
drawn into rail cars during unloading must be regulated in
temperature and cleaned of contaminants, such units have not been
fully effective in conditioning the ambient air by sterilizing,
filtering and heating it prior to being directed into the head
space of the railway car above the perishable food product.
While stationary and portable air purifiers have been known, such
as those described in U.S. Pat. No. 3,757,479 to Sievers and U.S.
Pat. No. 4,786,812 to Humphreys, these have been proposed for use
in offices, hospitals, food processing centers and the like.
However, in germicidal ultraviolet lamp units have not been
combined with mechanical filtering and temperature control to
optimize the conditioning of ambient air received within a rail car
unloading of perishable food products.
Accordingly, it is an object of the present invention to provide an
aspiration unit for conditioning air during rail car unloading of
perishable food products which does not have the disadvantages
encountered in the prior art units.
It is another object of the invention to provide an aspiration unit
of the type under discussion which is simple in construction and
economical to manufacture.
It is still another object of the present invention to provide an
aspiration unit for use with rail cars which is both effective to
remove large contaminants, such as insects, dust, air born yeast
and mold spores, as well as bacterial contaminants.
It is yet another object of the present invention to provide an
aspiration unit of the type under discussion which provides
mechanical filtering, temperature control as well as ultraviolet
exposure to ambient air before it is permitted to enter into the
head space inside a rail car during removal of the contents
thereof.
It is a further object of the present invention to provide an
aspiration unit as suggested in the previous objects which can be
easily positioned in place within a vent structure or access port
of a rail car prior to the unloading of perishable food products,
and easily removable after unloading has terminated. It is still a
further object of the present invention to provide an aspiration
unit as in the foregoing objects which can be utilized during
extreme ambient temperature conditions, without materially
affecting the effectiveness of the unit.
In order to achieve the above objects, as well as others which will
become apparent hereafter, a tank car unloading aspiration unit in
accordance with the present invention for conditioning air received
within the head space inside a tank car during removal of the
contents of the tank car and replacement of the removed contents
with the air comprises an air transfer portion configurated and
dimensioned to be received within an access port in the roof of a
rail tank car. Inlet conduit means is provided for directing
conditioned air into the head space and outlet conduit means for
removing air from the head space. Cover means is provided for
covering the aspiration unit, and intake means for admitting
ambient air into the unit. Conditioning means between said cover
means and said air transfer portion condition the ambient air by
heating the air to a temperature within a predetermined range and
exposing the air to electromagnetic radiation. Air movement means
is provided for drawing ambient air through said intake means and
expelling the conditioned air through said inlet conduit means
after passage of the ambient air through said conditioning
means.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present invention
will be readily appreciated as the same become better understood by
reference to the following detailed description when considered in
connection with the accompanying drawings, in which:
FIG. 1 is a perspective view of a rail car on which an unloading
aspiration unit in accordance with the present invention is mounted
through an access port or rail car manhole;
FIG. 2 is a perspective view of the unloading aspiration unit shown
in FIG. 1, shown enlarged and from an angular view below the
unit;
FIG. 3 is an exploded perspective view showing the various elements
or components of the unloading aspiration unit shown in FIG. 2,
showing the manner in which the various portions of the unit are
arranged relative to each other;
FIG. 4 is a cross-sectional view of the unloading aspiration unit
shown in FIG. 2, taken along line 4--4 in FIG. 2;
FIG. 5 is a cross-sectional view of the unloading aspiration unit
shown in FIG. 2, taken along 5--5 in FIG. 2;
FIG. 6 is an enlarged top elevational view of the radiation
chamber, partially broken away to show the insulation within the
wall of the radiation unit and showing details of the cover plate
and the means of mounting the unit on the rail car; and
FIG. 7 is an electrical schematic diagram illustrating the
electrical circuit which is used in conjunction with the unloading
aspiration unit of the previous figures.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now specifically to the drawings, in which identical or
similar parts are designated by the same reference numerals
throughout, and first referring to FIG. 1, there is shown a rail
tank car 10 of the type in which, for example, corn syrup is
transported. The rail car 10 includes a tank or container 12 which
serves as a storage vessel from which the transported product, such
as corn syrup, can be off-loaded into stainless steel tank trucks
which in turn deliver the product to the ultimate customers. The
tank or container 12 is typically provided with an access port,
manhole, or manway hole 14 which can be selectively closed with a
cover 16 into sealing engagement with the access port by movement
about a hinge 18. Such sealing can be effected with any
conventional ring gasket, such as those made of neoprene or
synthetic rubber may be used.
In order to provide proper venting to the rail car when pumping off
syrup and maintenance of good air quality in the air space above
the syrup inside the rail car, an unloading aspiration unit 20 in
accordance with the present invention is provided which is
dimensioned to be mounted on the rail car 10 as shown, with at
least a portion of the aspiration unit received within the tank or
container 12 below the access port 14 and the rest of the unit
projecting upwardly above the tank or container. As suggested, when
syrup is removed from the rail car, air must be supplied to replace
the removed syrup. The air must be of good quality to protect the
integrity of the syrup product. The function of the aspiration unit
20 is to remove dust, dirt and microbiological contaminations which
may contaminate the syrup or other food product, and which
eliminates condensation and dripping in the rail car which could
lead to mold and bacterial growth when air is drawn into the rail
car while the syrup is unloaded.
Referring to FIG. 2, the unloading aspiration unit 20 includes a
rail car nozzle 24 which is received within the manhole or manway
hole of the access port 14 and is, therefore, received within the
tank or container 12 when the aspiration unit is mounted on the
rail car. While the rail car nozzle 24 is disposed below the cover
plate 22, the remainder of the aspiration unit is disposed above
the cover plate.
At the top of the aspiration unit 20 there is provided a weather
shield, hood or cover 26 which has four walls and a pitched roof,
as shown, and is provided with an apertured plate member 26' (shown
in FIG. 3) which facilitates the lifting and positioning of the
aspiration unit.
Also referring to FIGS. 3-5, the hood 26 encloses, in spaced
relation, a fan chamber 28 which is supported on a heating chamber
30, which itself is mounted on an irradiation chamber 32 secured to
the cover plate 22. As shown in the Figures, the walls of the hood
26 are substantially uniformly spaced from the walls of the fan
chamber 28 and mounted thereto by means of mounting standoffs or
spacers 34 to provide an air inlet clearance space 36 which extends
about the periphery of the unit. Referring to FIGS. 3-5, the fan
chamber 38 has a substantially rectangular opening at the upper end
thereof which is defined by a recessed peripheral ledge 38.
Upwardly projecting transverse spacers 40 are provided on at least
one pair of opposing sides of the fan chamber 28, to provide a
ledge for securely receiving an air filter 42. The air filter 42
includes a frame 44 dimensioned to be received within the recessed
peripheral ledge 38 and a porous filter material 46 of any suitable
type for removing undesirable contaminants.
Referring to FIG. 4, there is provided within the fan chamber 28 a
fan 48 which has its exhaust port substantially aligned with an
opening 50, the fan functioning to direct air that is passed
through the filter 42 through the opening 50 into the heating
chamber 30.
Provided within the heating chamber 30 is a support platform 52 on
which three heaters 54, 56 and 58, to be more fully described in
connection with FIG. 7, are arranged substantially in the path of
the air flow AF which is forced through the heating chamber 30 by
the fan 48.
The air is then directed into the irradiation chamber 32 and
exposed to at least one ultra violet lamp 60, two being shown
mounted on a support bracket 62.
The rail car nozzle 24 is provided with two air inlet pipes 64,
each having an upper inlet opening 64a between an associated ultra
violet lamp 60 and a wall of the radiation chamber 32, and having
an air outlet 64b which is arranged at substantially a right angle
to the downwardly directed inlet tube or pipe 64 so as to release
the conditioned air in a substantially horizontal direction. As
best shown in FIGS. 5 and 6, the upper inlet portion 64a of the
inlet tube or pipe 64 is so arranged in relation to the ultra
violet lamps that the stream of air AF is forced to pass through
the ultra violet lamp 60 in order to reach the upper lamp portion
64a. In this manner, it is assured that the air will be exposed to
the ultra violet lamps. Excess air is received within the flared
end 66a of air outlet pipe 66 of the rail car nozzle 24, and an air
outlet pipe 66b connects the air outlet pipe 66 with an air outlet
pipe portion 66c which exhausts excess air exteriorally of the tank
or container 12 above the cover plate 22. Outlet pipe portion 66c
should be provided with a screen (not shown) to prevent insects
from entering the unit.
As is also clear from FIGS. 4 and 5, the cover plate 22 is
supported, during use of the aspiration unit, on the upper surface
14' of the rail car or access port.
Mounted on one wall of the irradiation chamber 32 is a thermostat
and ballast housing or electrical box 68 which has an access door
panel 70 and a power line 72 which can be connected to a source of
power by means of a plug 74.
Referring to FIG. 6, the cover plate 22 is shown to be provided
with six equally spaced U-shaped retaining members which have a
length dimension L of approximately two inches and which have a
spacing between the legs or arms thereof S equal to approximately
1.5 inches. These retaining members can be used to clamp the cover
22 in sealing engagement to the access port 14 by using the same
bolts as are used to hold down the cover 16. The walls of the
irradiation chamber 32 are advantageously provided with insulation
78, as shown. Also, the upper ends or portion 64a of the air inlet
tubes or pipes 64 are provided with a mesh screen 80 which prevents
larger particles and contaminants from entering into the rail
car.
In FIG. 7, the electrical circuit for controlling the various
electrical components of the device is illustrated. As will be
noted, the various electrical elements or components are connected
between AC power lines L1 and L2, with the neutral line N also
being provided. In one leg, the two heaters 54 and 56 are shown
connected and parallel and fuses F1 and F2 being provided at both
ends of the series connection of the heaters and thermostat T1. The
third heater 58 is connected between the same power lines and is
protected by fuses F3 and F4. Both heater circuits are provided
with a temperature regulating means in the nature of a thermostat,
T1 for the first two heaters and T2 for the second heater. The fan
48 is connected between the AC line L1 and the neutral line N, and
is protected by fuses F5 and F6. Each of the ultra violet lamps 60
is provided with a similar circuit, connected in parallel across
the AC power lines L1 and L2, each ultra violet lamp being
connected to a ballast B and protected on each side by fuses F7, F8
and F9, F10 respectively.
The operation of the unloading aspiration unit will now be
described. When the rail car is to be unloaded, the cover 16 is
opened to expose the access port 14. The entire aspiration unit is
thereupon lowered through the rail car manhole or manway hole and
positioned to provide sealing contact between the lower surface of
the cover plate 22 and the upper surface of the access port 14. The
manner in which such seal is provided is well known to those
skilled in the art and will not be discussed in detail.
After the aspiration unit 20 is mounted in place, as shown in FIGS.
1, 4 and 5, the electrical box 68 is connected to suitable AC power
lines so as to provide power across the parallel circuits shown in
FIG. 7. When 220 volts is applied to the control circuit, the fan
48 is immediately energized and air is drawn into the aspiration
unit through the air inlet space or clearance 36, which air is
forced through the air filter 42. The ballasts B also immediately
turn on the ultra violet lamps, and these lamps remain on, as does
the fan 48, until the AC power is removed. Typically, the fan
provides approximately 150 cubic feet per minute ("cfm") of air to
the unit. This volume of air will be heated as it passes through
the heaters 54, 56 and 58. The thermostats T1 and T2 are adjusted
in order to maintain the air within the range of approximately 85
.degree. F.-95.degree. F. The heater 58 will open, i.e. the power
will be shut off (via temperature switch of the thermostat) when
the temperature is over 95.degree. F. The two heaters 54 and 56, on
the other hand, are adjusted to open when the temperature of the
air is over 85.degree. F., i.e. heater 58 is the only heater which
is on. If the temperature is below 85.degree. F., then all three of
the heaters 54, 56 and 58 are on. It has been found that at
temperatures less than 40.degree. F. spores, bacteria and yeast are
not killed when exposed to the UV light, whereas significant kill
rates take place above 40.degree. F. To provide a 100% kill
condition, the air temperature must be heated to approximately
between 80.degree.-90.degree. F.
The temperature probes for the thermostats are located in the
irradiation chamber (not shown) where the ultra violet lamps are
located below the heating chamber.
It should be clear that with the unloading aspiration unit 20 in
accordance with the present invention, ambient air can be drawn
into the unit in order to condition the same and expelled after
passage of the air through the unit and through the interior of the
tank car.
What has been described is a preferred embodiment of the present
invention in which modification and changes may be made without
departing from the spirit and scope of the accompanying claims.
* * * * *